The possibility for using smart pills or miniature microelectronic capsules which have the capability to transmit diagnostic data from the gastrointestinal (GI) tract has been the subject of increasing scholarly and practical interest. Alternatively to the capsule endoscopy concept, new smart pill designs do not necessarily have to include imaging modality, since many other physiological, electrical, chemical, and mechanical phenomena in internal organs in general, or in the gut in particular (for example, pH, pressure, intraluminal impedance, etc.) could be investigated using this-non-invasive technique.
Examples of magnetically driven capsules used in human body diagnosis and treatment include: Ueda, U.S. Pat. No. 5,681,260, which describes a capsule type endoscope that carries a video camera, transmitter, receiver and magnet. The transmitter and receiver communicate with an exterior transmitter and receiver to deliver video images to a display. An exterior magnetic force generator with a capsule locating sensor and controller controls magnetic force on the magnet and hence on the capsule. Temperature and pH sensors may be carried on the capsule. Jin, U.S. Pat. No. 6,776,165, describes a navigation system and navigatable capsules which are useful for remote-controlled imaging, biopsy and programmable drug release within the body of an animal. The components of the system comprise a capsule dimensioned and shaped to move within the body. An anisotropic magnetic component is mechanically coupled to the capsule to move or orient the body in relation to an applied magnetic field, and a magnetic field generating system external of the body generates a three dimensionally oriented magnetic field within the body to move or orient capsule. Wakefield, 2004, US Pat App. 20040199054, discloses a general concept of magnetically propelled capsule endoscopy, including the concept of using magnets for movement and directional control and position sensors. It envisions control by an externally-generated magnetic field.
However, the issue of controlled affixing (holding) or steering such microelectronic capsules to and from particular positions in the gastrointestinal (GI) tract has not been satisfactorily resolved by these teachings.